Circuit-interrupting device.



CFAALBORG.

CIRCUIT INTERRUPTING DEVICE.

APPUCATlON FILED JULY 29. 1913.

1 1 8 1 ,2O() Patented May 2, 1916.

iNVENTOR MM ATTORNEY UNITED, s'r rns CHRISTIAN AAL'BOIRG, on WILKINSBfiRG, PENNSYLVANIA, assrsnoa To wnsrnt HOUSE nnnc'rmc AND mnnnrscrnmns cor/teeny, 'A conroanrronor enn- VANIA.

CIRCUITJNTEBRUPTING DEVICE.

Specification of Letters Patent.

Latent d trays, i at 17 Application filed July 23, 1913. Serial No; 781,739.

To all whom it may concern:

Be it known that I, CHRISTIAN AALBORG, a citizen of theUnited States, and a resident of Wilkinsburg, in the county of Alleghe ny and State of Pennsylvania, have invented a new and useful Improvement in Circuit-Interrupting Devices, of which the following is a specification.

My invention relates to circuit interrupters and particularly to knife blade switches of'the double throw quick-break type, and it has for its object to provide a double-thuv quick-break knife blade switch of strong but inexpensive construction.

Heretofore the quick-break members of double-throw knife-blade switches have been pivoted at different points on the main I knife blade and have been yielding'ly held against the main knife blade by springs. This required a plurality of holes in the main knife blade and necessitated the use of at least two springs on each of its sides. As heretofore provided, the quick-break knife blades were of a solid structure and, consequently, the hinged or angular portions required complicated machining. In my invention, I provide an easily constructed double-throw quick-break knife-blade switch that requires only one pivot member for pivoting the quick-break knife blades. Since the springs, as provided in my device, need not be attached to the main knife-blade, the construction may be so simplified as to permit of easy and quick repair.

I further provide a construction, independent of the springs, for limiting the travel of the quick-break knife blades from their initial positions adjacent to the main knife blade. I

Figure 1 of the accompanying drawing is a plan view of a quick-break knife blade before it is bent into its final form. Fig. 2 is a side elevation of a completed blade. Fig. 3 is a front elevation of the completed blade and Fig. 4 is a side elevation of a complete double-throw quick-break. kni feblade switch embodying my invention.

Referring to the drawing, my invention comprises a main blade 1 of a double-throw knife-blade switch, a member 2 to which the blade 1 is pivoted and stationary contact members 3 and 4, all of which are mounted on a base 5. Each of the anvil-- iary quick-break blades 6 and 7 is formed from a flat piece of metal Sjas shown in Fig. 1, by folding it laterally; on a line 1+1 to provide two arms 9 an-dt'lll) ofimeq nal' length, the arm 9 having a holettherein to receive a pin 11 for pivoting-it tothe-maifi blade 1. The arms S) andlO arespacednpart' to embrace the blade lend. the walls formed at their" junctions ivith' t he bod'y portions are inclined at sueh'angles' constitute stops for engagingthe"corre-f spending edges of the inaiiifbladewhen moved outwardly to the" a-ll'ovable degree. The quick-break blades (3 and 7 are located at opposite edges of the main blade 1 so that only one pivoting pin is rctplired. The re spective ends of a spring 13 are attached to pins it and 15 that project laterally from the sides of the members and 7, a second spring (not shown) being similarly con nected to the other sides of the (prick-break knife blades to hold tl the main blade.

The operation of my invention is ob vious to any one skilled in the art, and its advantages will be readily understood. \Vhen a quiclcbreak blade snaps out of its stationary contact terminal. it pivots around the pivotal point 11 on one of its arms. be ing guided by the rounded part of the other arm. The action of the (lllll'kdH'PltlC blade is similar to other (prick-break blades in that the main blade. W hen \vitlulrau'n, leaves the (prick-break blade in contact. until the main blade has traveled such a distan e that the spri'r 13 overcomes the friction with the stationary contact tm'minal or until the inclined portion 1-2 engages the main blade to force the auxiliary blade. out of engagement with the contact terl'uinal.

Minor variations as to the size. shape and arrangement of the various parts may he made within the scope of the appended claims Without departing from my invention.

I claim as my invention:

1. In a circuit-interrupting device, the combination with contact jaws and a doublet-hrow knife-blade member, of an auxiliary quick-break knife-blade member at each edge thereof and attached thereto by a single means, said (prick-break knife-blade members severally comprising a folded metal piece having in .erally z rojecting arms of unequal length provided with no yielding'ly against Y rounded ends, the' said arms being of such length that the rounded ends serve as bearings' Y p 2. In a circuit-interrupting device, the

combination with contact jaws and'a main double-throw knife-blade member, of quick break blades attached to said main .member andLSeveraHy eomprisinga. metal piece hav-' ing arms of unequal length, said arms being provided with rounded ends that constitute bearingsfor each other. 7

3."In a circuit-interrupting device, the

combination with contact jaws and a main double-throw knife-blade member, of quickbreak blades attached-to said main member at a single point and severally comprising a metal. piece having arms of unequal length,

' said arms being provided with rounded ends that constitute bearings for each other,

"4. A' double-throw knife-blade s'witc'h comprising a main knife-blade member and two quick-break blades attached thereto at a single point, said quick-break blades severally comprising a metal piece having'two arms of unequal length provided with rounded, ends, the rounded ends of the arms v on one blade being adapted to constitute the bearings of the other blade.

5. A double-throw switch comprising a main kn'ife-blademember, two quick-break blades and means interposed between the quick-break blades for normally holding them adjacent to the said main blade, said,

CHRISTIAN AALBORG.

i Witnesses: I t

AL A G. CORRAO, W B. B. HINES. 

